The Google offices in Seoul were raided by the antitrust officials in South Korea. The company is suspected of conducting anticompetitive behavior with its Android smartphone platform, Reuters reports.

The complaint was filled by NHN Corp and Daum Communications Corp, who say Android smartphones have Google’s search engine installed as a default navigation tool and are “systematically designed” to make it virtually impossible to switch to another option.

Google responded that using the Google search or any of the other Google applications isn’t mandatory and every manufacturer can opt out of them if they like. The Mountain View company has promised to cooperate with Korean Fair Trade Commission and help with the investigation.